Retired Document
Important: This sample code may not represent best practices for current development. The project may use deprecated symbols and illustrate technologies and techniques that are no longer recommended.
Relevant replacement documents include:
PublicUtility/CABufferList.cpp
/* |
File: CABufferList.cpp |
Abstract: CABufferList.h |
Version: 1.1 |
Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple |
Inc. ("Apple") in consideration of your agreement to the following |
terms, and your use, installation, modification or redistribution of |
this Apple software constitutes acceptance of these terms. If you do |
not agree with these terms, please do not use, install, modify or |
redistribute this Apple software. |
In consideration of your agreement to abide by the following terms, and |
subject to these terms, Apple grants you a personal, non-exclusive |
license, under Apple's copyrights in this original Apple software (the |
"Apple Software"), to use, reproduce, modify and redistribute the Apple |
Software, with or without modifications, in source and/or binary forms; |
provided that if you redistribute the Apple Software in its entirety and |
without modifications, you must retain this notice and the following |
text and disclaimers in all such redistributions of the Apple Software. |
Neither the name, trademarks, service marks or logos of Apple Inc. may |
be used to endorse or promote products derived from the Apple Software |
without specific prior written permission from Apple. Except as |
expressly stated in this notice, no other rights or licenses, express or |
implied, are granted by Apple herein, including but not limited to any |
patent rights that may be infringed by your derivative works or by other |
works in which the Apple Software may be incorporated. |
The Apple Software is provided by Apple on an "AS IS" basis. APPLE |
MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION |
THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS |
FOR A PARTICULAR PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND |
OPERATION ALONE OR IN COMBINATION WITH YOUR PRODUCTS. |
IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL |
OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
INTERRUPTION) ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION, |
MODIFICATION AND/OR DISTRIBUTION OF THE APPLE SOFTWARE, HOWEVER CAUSED |
AND WHETHER UNDER THEORY OF CONTRACT, TORT (INCLUDING NEGLIGENCE), |
STRICT LIABILITY OR OTHERWISE, EVEN IF APPLE HAS BEEN ADVISED OF THE |
POSSIBILITY OF SUCH DAMAGE. |
Copyright (C) 2012 Apple Inc. All Rights Reserved. |
*/ |
#include "CABufferList.h" |
#include "CAByteOrder.h" |
void CABufferList::AllocateBuffers(UInt32 nBytes) |
{ |
if (nBytes <= GetNumBytes()) return; |
if (mABL.mNumberBuffers > 1) |
// align successive buffers for Altivec and to take alternating |
// cache line hits by spacing them by odd multiples of 16 |
nBytes = ((nBytes + 15) & ~15) | 16; |
UInt32 memorySize = nBytes * mABL.mNumberBuffers; |
Byte *newMemory = new Byte[memorySize], *p = newMemory; |
memset(newMemory, 0, memorySize); // get page faults now, not later |
AudioBuffer *buf = mABL.mBuffers; |
for (UInt32 i = mABL.mNumberBuffers; i--; ++buf) { |
if (buf->mData != NULL && buf->mDataByteSize > 0) |
// preserve existing buffer contents |
memcpy(p, buf->mData, buf->mDataByteSize); |
buf->mDataByteSize = nBytes; |
buf->mData = p; |
p += nBytes; |
} |
Byte *oldMemory = mBufferMemory; |
mBufferMemory = newMemory; |
mBufferCapacity = nBytes; |
delete[] oldMemory; |
} |
void CABufferList::AllocateBuffersAndCopyFrom(UInt32 nBytes, CABufferList *inSrcList, CABufferList *inSetPtrList) |
{ |
if (mABL.mNumberBuffers != inSrcList->mABL.mNumberBuffers) return; |
if (mABL.mNumberBuffers != inSetPtrList->mABL.mNumberBuffers) return; |
if (nBytes <= GetNumBytes()) { |
CopyAllFrom(inSrcList, inSetPtrList); |
return; |
} |
inSetPtrList->VerifyNotTrashingOwnedBuffer(); |
UInt32 fromByteSize = inSrcList->GetNumBytes(); |
if (mABL.mNumberBuffers > 1) |
// align successive buffers for Altivec and to take alternating |
// cache line hits by spacing them by odd multiples of 16 |
nBytes = ((nBytes + 15) & ~15) | 16; |
UInt32 memorySize = nBytes * mABL.mNumberBuffers; |
Byte *newMemory = new Byte[memorySize], *p = newMemory; |
memset(newMemory, 0, memorySize); // make buffer "hot" |
AudioBuffer *buf = mABL.mBuffers; |
AudioBuffer *ptrBuf = inSetPtrList->mABL.mBuffers; |
AudioBuffer *srcBuf = inSrcList->mABL.mBuffers; |
for (UInt32 i = mABL.mNumberBuffers; i--; ++buf, ++ptrBuf, ++srcBuf) { |
if (srcBuf->mData != NULL && srcBuf->mDataByteSize > 0) |
// preserve existing buffer contents |
memmove(p, srcBuf->mData, srcBuf->mDataByteSize); |
buf->mDataByteSize = nBytes; |
buf->mData = p; |
ptrBuf->mDataByteSize = srcBuf->mDataByteSize; |
ptrBuf->mData = p; |
p += nBytes; |
} |
Byte *oldMemory = mBufferMemory; |
mBufferMemory = newMemory; |
mBufferCapacity = nBytes; |
if (inSrcList != inSetPtrList) |
inSrcList->BytesConsumed(fromByteSize); |
delete[] oldMemory; |
} |
void CABufferList::DeallocateBuffers() |
{ |
AudioBuffer *buf = mABL.mBuffers; |
for (UInt32 i = mABL.mNumberBuffers; i--; ++buf) { |
buf->mData = NULL; |
buf->mDataByteSize = 0; |
} |
if (mBufferMemory != NULL) { |
delete[] mBufferMemory; |
mBufferMemory = NULL; |
mBufferCapacity = 0; |
} |
} |
static void show(const AudioBufferList &abl, int framesToPrint, int wordSize, const char *label, const char *fmtstr=NULL) |
{ |
printf("%s %p (%d fr%s):\n", label ? label : "AudioBufferList", &abl, framesToPrint, fmtstr ? fmtstr : ""); |
const AudioBuffer *buf = abl.mBuffers; |
for (UInt32 i = 0; i < abl.mNumberBuffers; ++i, ++buf) { |
printf(" [%2d] %5dbytes %dch @ %p", (int)i, (int)buf->mDataByteSize, (int)buf->mNumberChannels, buf->mData); |
if (framesToPrint && buf->mData != NULL) { |
printf(":"); |
Byte *p = (Byte *)buf->mData; |
for (int j = framesToPrint * buf->mNumberChannels; --j >= 0; ) |
switch (wordSize) { |
case 0: // native float |
printf(" %6.3f", *(Float32 *)p); |
p += sizeof(Float32); |
break; |
// positive: big endian |
case 1: |
case -1: |
printf(" %02X", *p); |
p += 1; |
break; |
case 2: |
printf(" %04X", CFSwapInt16BigToHost(*(UInt16 *)p)); |
p += 2; |
break; |
case 3: |
printf(" %06X", (p[0] << 16) | (p[1] << 8) | p[2]); |
p += 3; |
break; |
case 4: |
printf(" %08X", (unsigned int)CFSwapInt32BigToHost(*(UInt32 *)p)); |
p += 4; |
break; |
case 10: |
printf(" %6.3f", CASwapFloat32BigToHost(*(Float32 *)p)); |
p += sizeof(Float32); |
break; |
case -2: |
printf(" %04X", CFSwapInt16LittleToHost(*(UInt16 *)p)); |
p += 2; |
break; |
case -3: |
printf(" %06X", (p[2] << 16) | (p[1] << 8) | p[0]); |
p += 3; |
break; |
case -4: |
printf(" %08X", (unsigned int)CFSwapInt32LittleToHost(*(UInt32 *)p)); |
p += 4; |
break; |
case -10: |
printf(" %6.3f", CASwapFloat32LittleToHost(*(Float32 *)p)); |
p += sizeof(Float32); |
break; |
} |
} |
printf("\n"); |
} |
} |
void CAShowAudioBufferList(const AudioBufferList &abl, int framesToPrint, const AudioStreamBasicDescription &asbd, const char *label) |
{ |
CAStreamBasicDescription fmt(asbd); |
int wordSize = 1; |
char fmtstr[80] = { 0 }; |
if (fmt.mFormatID == kAudioFormatLinearPCM) { |
if (fmt.mFormatFlags & kLinearPCMFormatFlagIsFloat) { |
if (fmt.mBitsPerChannel == 32) { |
if (fmt.mFormatFlags & kLinearPCMFormatFlagIsBigEndian) { |
wordSize = 10; |
strcpy(fmtstr, ", BEF"); |
} else { |
wordSize = -10; |
strcpy(fmtstr, ", LEF"); |
} |
} |
} else { |
wordSize = fmt.SampleWordSize(); |
if (wordSize > 0) { |
int fracbits = (asbd.mFormatFlags & kLinearPCMFormatFlagsSampleFractionMask) >> kLinearPCMFormatFlagsSampleFractionShift; |
if (fracbits > 0) |
sprintf(fmtstr, ", %d.%d-bit", (int)asbd.mBitsPerChannel - fracbits, fracbits); |
else |
sprintf(fmtstr, ", %d-bit", (int)asbd.mBitsPerChannel); |
if (!(fmt.mFormatFlags & kLinearPCMFormatFlagIsBigEndian)) { |
wordSize = -wordSize; |
strcat(fmtstr, " LEI"); |
} else { |
strcat(fmtstr, " BEI"); |
} |
} |
} |
} |
show(abl, framesToPrint, wordSize, label, fmtstr); |
} |
void CAShowAudioBufferList(const AudioBufferList &abl, int framesToPrint, int wordSize, const char *label) |
{ |
show(abl, framesToPrint, wordSize, label); |
} |
extern "C" void CAShowAudioBufferList(const AudioBufferList *abl, int framesToPrint, int wordSize) |
{ |
show(*abl, framesToPrint, wordSize, NULL); |
} |
// if the return result is odd, there was a null buffer. |
extern "C" int CrashIfClientProvidedBogusAudioBufferList(const AudioBufferList *abl, bool nullok) |
{ |
const AudioBuffer *buf = abl->mBuffers, *bufend = buf + abl->mNumberBuffers; |
int sum = 0; // defeat attempts by the compiler to optimize away the code that touches the buffers |
int anyNull = 0; |
for ( ; buf < bufend; ++buf) { |
const int *p = (const int *)buf->mData; |
if (p == NULL) { |
anyNull = 1; |
if (nullok) continue; |
} |
// if client provided a bogus ABL, we want to crash here |
unsigned datasize = buf->mDataByteSize; |
if (datasize >= sizeof(int)) { |
// turn off the analyzer warning in this case since crash if any, is intended |
#ifndef __clang_analyzer__ |
sum += p[0]; |
sum += p[datasize / sizeof(int) - 1]; |
#endif |
} |
} |
return anyNull | (sum & ~1); |
} |
Copyright © 2012 Apple Inc. All Rights Reserved. Terms of Use | Privacy Policy | Updated: 2012-10-16